SQLite

** "chunks" such that the total DB file size may exceed the maximum
** file size of the underlying file system.
**
*/
#include "sqlite3.h"
#include <string.h>
#include <assert.h>

#include "test_multiplex.h"

#ifndef SQLITE_CORE
  #define SQLITE_CORE 1  /* Disable the API redefinition in sqlite3ext.h */
#endif
#include "sqlite3ext.h"

/* 
** These should be defined to be the same as the values in 
** sqliteInt.h.  They are defined seperately here so that
** the multiplex VFS shim can be built as a loadable 
** module.
*/
#define UNUSED_PARAMETER(x) (void)(x)
#define MAX_PAGE_SIZE       0x10000
#define DEFAULT_SECTOR_SIZE 0x1000

/*
** For a build without mutexes, no-op the mutex calls.
*/
#if defined(SQLITE_THREADSAFE) && SQLITE_THREADSAFE==0
#define sqlite3_mutex_alloc(X)    ((sqlite3_mutex*)8)
#define sqlite3_mutex_free(X)
#define sqlite3_mutex_enter(X)
#define sqlite3_mutex_try(X)      SQLITE_OK
#define sqlite3_mutex_leave(X)
#define sqlite3_mutex_held(X)     ((void)(X),1)
#define sqlite3_mutex_notheld(X)  ((void)(X),1)
#endif /* SQLITE_THREADSAFE==0 */


/************************ Shim Definitions ******************************/

#define SQLITE_MULTIPLEX_VFS_NAME "multiplex"

/* This is the limit on the chunk size.  It may be changed by calling
** the xFileControl() interface.  It will be rounded up to a 
** multiple of MAX_PAGE_SIZE.  We default it here to 1GB.
*/
#define SQLITE_MULTIPLEX_CHUNK_SIZE (MAX_PAGE_SIZE*16384)

/* Default limit on number of chunks.  Care should be taken
** so that values for chunks numbers fit in the SQLITE_MULTIPLEX_EXT_FMT
** format specifier. It may be changed by calling
** the xFileControl() interface.
*/
#define SQLITE_MULTIPLEX_MAX_CHUNKS 32

/************************* Utility Routines *********************************/
/*
** Acquire and release the mutex used to serialize access to the
** list of multiplexGroups.
*/
static void multiplexEnter(void){ sqlite3_mutex_enter(gMultiplex.pMutex); }
static void multiplexLeave(void){ sqlite3_mutex_leave(gMultiplex.pMutex); }

/*
** Compute a string length that is limited to what can be stored in
** lower 30 bits of a 32-bit signed integer.
**
** The value returned will never be negative.  Nor will it ever be greater
** than the actual length of the string.  For very long strings (greater
** than 1GiB) the value returned might be less than the true string length.
*/
int multiplexStrlen30(const char *z){
  const char *z2 = z;
  if( z==0 ) return 0;
  while( *z2 ){ z2++; }
  return 0x3fffffff & (int)(z2 - z);
}

/* Translate an sqlite3_file* that is really a multiplexGroup* into
** the sqlite3_file* for the underlying original VFS.
*/
static sqlite3_file *multiplexSubOpen(multiplexConn *pConn, int iChunk, int *rc, int *pOutFlags){
  multiplexGroup *pGroup = pConn->pGroup;
  sqlite3_vfs *pOrigVfs = gMultiplex.pOrigVfs;        /* Real VFS */

    *rc = SQLITE_OK;
    return pSubOpen;
  }
  *rc = SQLITE_FULL;
  return NULL;
}

/*
** This is the implementation of the multiplex_control() SQL function.
*/
static void multiplexControlFunc(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){


  int rc = SQLITE_OK;
  sqlite3 *db = sqlite3_context_db_handle(context);
  int op;
  int iVal;

  if( !db || argc!=2 ){ 
    rc = SQLITE_ERROR; 

      case 2: 
        op = MULTIPLEX_CTRL_SET_CHUNK_SIZE; 
        break;
      case 3: 
        op = MULTIPLEX_CTRL_SET_MAX_CHUNKS; 
        break;
      default:
        rc = SQLITE_NOTFOUND;
        break;
    }
  }
  if( rc==SQLITE_OK ){
    rc = sqlite3_file_control(db, 0, op, &iVal);
  }
  sqlite3_result_error_code(context, rc);
}

/*
** This is the entry point to register the auto-extension for the 
** multiplex_control() function.
*/
static int multiplexFuncInit(
  sqlite3 *db, 
  char **pzErrMsg, 
  const sqlite3_api_routines *pApi
){
  int rc;
  rc = sqlite3_create_function(db, "multiplex_control", 2, SQLITE_ANY, 
      0, multiplexControlFunc, 0, 0);
  return rc;
}

/************************* VFS Method Wrappers *****************************/

/*
** This is the xOpen method used for the "multiplex" VFS.

  int *pOutFlags             /* Flags showing results of opening */
){
  int rc;                                        /* Result code */
  multiplexConn *pMultiplexOpen;                 /* The new multiplex file descriptor */
  multiplexGroup *pGroup;                        /* Corresponding multiplexGroup object */
  sqlite3_file *pSubOpen;                        /* Real file descriptor */
  sqlite3_vfs *pOrigVfs = gMultiplex.pOrigVfs;   /* Real VFS */
  int nName = multiplexStrlen30(zName);
  int i;
  int sz;

  UNUSED_PARAMETER(pVfs);

  /* We need to create a group structure and manage
  ** access to this group of files.
  */
  multiplexEnter();
  pMultiplexOpen = (multiplexConn*)pConn;
  /* allocate space for group */
  sz = sizeof(multiplexGroup)                                /* multiplexGroup */
     + (sizeof(sqlite3_file *)*SQLITE_MULTIPLEX_MAX_CHUNKS)  /* pReal[] */
     + (pOrigVfs->szOsFile*SQLITE_MULTIPLEX_MAX_CHUNKS)      /* *pReal */
     + SQLITE_MULTIPLEX_MAX_CHUNKS                           /* bOpen[] */
     + nName + 1;                                            /* zName */
#ifndef SQLITE_MULTIPLEX_EXT_OVWR
  sz += SQLITE_MULTIPLEX_EXT_SZ;
  assert(nName+SQLITE_MULTIPLEX_EXT_SZ < pOrigVfs->mxPathname);
#else
  assert(nName >= SQLITE_MULTIPLEX_EXT_SZ);
  assert(nName < pOrigVfs->mxPathname);
#endif

static int multiplexDelete(
  sqlite3_vfs *pVfs,         /* The multiplex VFS */
  const char *zName,         /* Name of file to delete */
  int syncDir
){
  sqlite3_vfs *pOrigVfs = gMultiplex.pOrigVfs;   /* Real VFS */
  int rc = SQLITE_OK;
  int nName = multiplexStrlen30(zName);
  int i;

  UNUSED_PARAMETER(pVfs);

  multiplexEnter();
  memcpy(gMultiplex.zName, zName, nName+1);
  for(i=0; i<SQLITE_MULTIPLEX_MAX_CHUNKS; i++){
    int rc2;
    int exists = 0;
    if( i ){
#ifdef SQLITE_MULTIPLEX_EXT_OVWR
        sqlite3_snprintf(SQLITE_MULTIPLEX_EXT_SZ+1, 
            gMultiplex.zName+nName-SQLITE_MULTIPLEX_EXT_SZ, 
            SQLITE_MULTIPLEX_EXT_FMT, i);
#else
        sqlite3_snprintf(SQLITE_MULTIPLEX_EXT_SZ+1, 
            gMultiplex.zName+nName, 
            SQLITE_MULTIPLEX_EXT_FMT, i);
#endif
    }
    rc2 = pOrigVfs->xAccess(pOrigVfs, gMultiplex.zName, 
        SQLITE_ACCESS_EXISTS, &exists);
    if( rc2==SQLITE_OK && exists){
      /* if it exists, delete it */
      rc2 = pOrigVfs->xDelete(pOrigVfs, gMultiplex.zName, syncDir);
      if( rc2!=SQLITE_OK ) rc = rc2;
    }else{
      /* stop at first "gap" */
      break;

      if( pGroup->bOpen[i] ){
        pSubOpen = pGroup->pReal[i];
        rc2 = pSubOpen->pMethods->xClose(pSubOpen);
        if( rc2!=SQLITE_OK ) rc = SQLITE_IOERR_TRUNCATE;
        pGroup->bOpen[i] = 0;
      }
#ifdef SQLITE_MULTIPLEX_EXT_OVWR
      sqlite3_snprintf(SQLITE_MULTIPLEX_EXT_SZ+1, 
          gMultiplex.zName+pGroup->nName-SQLITE_MULTIPLEX_EXT_SZ, 
          SQLITE_MULTIPLEX_EXT_FMT, i);
#else
      sqlite3_snprintf(SQLITE_MULTIPLEX_EXT_SZ+1, 
          gMultiplex.zName+pGroup->nName, 
          SQLITE_MULTIPLEX_EXT_FMT, i);
#endif
      rc2 = pOrigVfs->xDelete(pOrigVfs, gMultiplex.zName, 0);
      if( rc2!=SQLITE_OK ) rc = SQLITE_IOERR_TRUNCATE;
    }
    pSubOpen = multiplexSubOpen(p, (int)(size / pGroup->nChunkSize), &rc2, NULL);
    if( pSubOpen ){
      rc2 = pSubOpen->pMethods->xTruncate(pSubOpen, size % pGroup->nChunkSize);

        pSubOpen = pGroup->pReal[i];
      }else{
        sqlite3_vfs *pOrigVfs = gMultiplex.pOrigVfs;   /* Real VFS */
        int exists = 0;
        memcpy(gMultiplex.zName, pGroup->zName, pGroup->nName+1);
        if( i ){
#ifdef SQLITE_MULTIPLEX_EXT_OVWR
          sqlite3_snprintf(SQLITE_MULTIPLEX_EXT_SZ+1, 
              gMultiplex.zName+pGroup->nName-SQLITE_MULTIPLEX_EXT_SZ, 
              SQLITE_MULTIPLEX_EXT_FMT, i);
#else
          sqlite3_snprintf(SQLITE_MULTIPLEX_EXT_SZ+1, 
              gMultiplex.zName+pGroup->nName, 
              SQLITE_MULTIPLEX_EXT_FMT, i);
#endif
        }
        rc2 = pOrigVfs->xAccess(pOrigVfs, gMultiplex.zName, 
            SQLITE_ACCESS_EXISTS, &exists);
        if( rc2==SQLITE_OK && exists){
          /* if it exists, open it */
          pSubOpen = multiplexSubOpen(p, i, &rc, NULL);
        }else{
          /* stop at first "gap" */
          break;
        }

      break;
    case MULTIPLEX_CTRL_SET_CHUNK_SIZE:
      if( pArg ) {
        int nChunkSize = *(int *)pArg;
        if( nChunkSize<1 ){
          rc = SQLITE_MISUSE;
        }else{
          /* Round up to nearest multiple of MAX_PAGE_SIZE. */
          nChunkSize = (nChunkSize + (MAX_PAGE_SIZE-1));
          nChunkSize &= ~(MAX_PAGE_SIZE-1);
          pGroup->nChunkSize = nChunkSize;
          rc = SQLITE_OK;
        }
      }
      break;
    case MULTIPLEX_CTRL_SET_MAX_CHUNKS:
      if( pArg ) {

static int multiplexSectorSize(sqlite3_file *pConn){
  multiplexConn *p = (multiplexConn*)pConn;
  int rc;
  sqlite3_file *pSubOpen = multiplexSubOpen(p, 0, &rc, NULL);
  if( pSubOpen ){
    return pSubOpen->pMethods->xSectorSize(pSubOpen);
  }
  return DEFAULT_SECTOR_SIZE;
}

/* Pass xDeviceCharacteristics requests through to the original VFS unchanged.
*/
static int multiplexDeviceCharacteristics(sqlite3_file *pConn){
  multiplexConn *p = (multiplexConn*)pConn;
  int rc;

  memset(&gMultiplex, 0, sizeof(gMultiplex));
  return SQLITE_OK;
}

/***************************** Test Code ***********************************/
#ifdef SQLITE_TEST
#include <tcl.h>
extern const char *sqlite3TestErrorName(int);


/*
** tclcmd: sqlite3_multiplex_initialize NAME MAKEDEFAULT
*/
static int test_multiplex_initialize(
  void * clientData,

** VFS if makeDefault is non-zero.
**
** An auto-extension is registered which will make the function 
** multiplex_control() available to database connections.  This
** function gives access to the xFileControl interface of the 
** multiplex VFS shim.
**
** SELECT multiplex_control(<op>,<val>);
** 
**   <op>=1 MULTIPLEX_CTRL_ENABLE
**   <val>=0 disable
**   <val>=1 enable
** 
**   <op>=2 MULTIPLEX_CTRL_SET_CHUNK_SIZE
**   <val> int, chunk size
** 
**   <op>=3 MULTIPLEX_CTRL_SET_MAX_CHUNKS
**   <val> int, max chunks
**
** THIS ROUTINE IS NOT THREADSAFE.  Call this routine exactly once
** during start-up.
*/
extern int sqlite3_multiplex_initialize(const char *zOrigVfsName, int makeDefault);

do_test multiplex-1.9.5  { multiplex_set db main -1 16 }           {SQLITE_MISUSE}
do_test multiplex-1.9.6  { multiplex_set db main 31 16 }           {SQLITE_OK}
do_test multiplex-1.9.7  { multiplex_set db main 32768 100 }       {SQLITE_MISUSE}
do_test multiplex-1.9.8  { multiplex_set db main 1073741824 1 }    {SQLITE_OK}
do_test multiplex-1.9.9  { db close }                              {}
do_test multiplex-1.9.10 { sqlite3_multiplex_shutdown }            {SQLITE_OK}

do_test multiplex-1.10.1  { sqlite3_multiplex_initialize "" 1 }                                  {SQLITE_OK}
do_test multiplex-1.10.2  { sqlite3 db test.db }                                                 {}
do_test multiplex-1.10.3  { lindex [ catchsql { SELECT multiplex_control(2, 32768); } ] 0 }      {0}
do_test multiplex-1.10.4  { lindex [ catchsql { SELECT multiplex_control(3, -1); } ] 0 }         {1}
do_test multiplex-1.10.5  { lindex [ catchsql { SELECT multiplex_control(2, -1); } ] 0 }         {1}
do_test multiplex-1.10.6  { lindex [ catchsql { SELECT multiplex_control(2, 31); } ] 0 }         {0}
do_test multiplex-1.10.7  { lindex [ catchsql { SELECT multiplex_control(3, 100); } ] 0 }        {1}
do_test multiplex-1.10.8  { lindex [ catchsql { SELECT multiplex_control(2, 1073741824); } ] 0 } {0}
do_test multiplex-1.10.9  { db close }                                                           {}
do_test multiplex-1.10.10 { sqlite3_multiplex_shutdown }                                         {SQLITE_OK}

do_test multiplex-1.11.1  { sqlite3_multiplex_initialize "" 1 }               {SQLITE_OK}
do_test multiplex-1.11.2  { sqlite3 db test.db }                              {}
do_test multiplex-1.11.3  { sqlite3_multiplex_control db main enable 0  }     {SQLITE_OK}
do_test multiplex-1.11.4  { sqlite3_multiplex_control db main enable 1  }     {SQLITE_OK}
do_test multiplex-1.11.5  { sqlite3_multiplex_control db main enable -1 }     {SQLITE_OK}
do_test multiplex-1.11.6  { db close }                                        {}
do_test multiplex-1.11.7  { sqlite3_multiplex_shutdown }                      {SQLITE_OK}

do_test multiplex-1.12.1  { sqlite3_multiplex_initialize "" 1 }                           {SQLITE_OK}
do_test multiplex-1.12.2  { sqlite3 db test.db }                                          {}
do_test multiplex-1.12.3  { lindex [ catchsql { SELECT multiplex_control(1, 0); } ] 0 }   {0}
do_test multiplex-1.12.4  { lindex [ catchsql { SELECT multiplex_control(1, 1); } ] 0 }   {0}
do_test multiplex-1.12.5  { lindex [ catchsql { SELECT multiplex_control(1, -1); } ] 0 }  {0}
do_test multiplex-1.12.6  { db close }                                                    {}
do_test multiplex-1.12.7  { sqlite3_multiplex_shutdown }                                  {SQLITE_OK}

do_test multiplex-1.13.1  { sqlite3_multiplex_initialize "" 1 }                           {SQLITE_OK}
do_test multiplex-1.13.2  { sqlite3 db test.db }                                          {}
do_test multiplex-1.13.3  { lindex [ catchsql { SELECT multiplex_control(-1, 0); } ] 0 }  {1}
do_test multiplex-1.13.4  { lindex [ catchsql { SELECT multiplex_control(4, 1); } ] 0 }   {1}
do_test multiplex-1.13.6  { db close }                                                    {}
do_test multiplex-1.13.7  { sqlite3_multiplex_shutdown }                                  {SQLITE_OK}

#-------------------------------------------------------------------------
# Some simple warm-body tests with a single database file in rollback 
# mode:
#
#   multiplex-2.1.*: Test simple writing to a multiplex file.
#

      db close
      sqlite3_multiplex_shutdown
    } {SQLITE_OK}

  }
}

do_test multiplex-2.7.1  { multiplex_delete test.db }                                       {}
do_test multiplex-2.7.2  { sqlite3_multiplex_initialize "" 1 }                              {SQLITE_OK}
do_test multiplex-2.7.3  { sqlite3 db test.db }                                             {}
do_test multiplex-2.7.4  { lindex [ catchsql { SELECT multiplex_control(2, 65536); } ] 0 }  {0}
do_test multiplex-2.7.5  { lindex [ catchsql { SELECT multiplex_control(1, 0); } ] 0 }      {0}
do_test multiplex-2.7.6 { 
  execsql { 
    CREATE TABLE t1(a PRIMARY KEY, b);
    INSERT INTO t1 VALUES(1, randomblob(1000));
  }
} {}
# verify only one file, and file size is less than chunks size
do_test multiplex-2.7.7  { expr ([file size [multiplex_name test.db 0]] < 65536) } {1}
do_test multiplex-2.7.8  { file exists [multiplex_name test.db 1] }                {0}
do_test multiplex-2.7.9 { 
  execsql { 
    INSERT INTO t1 VALUES(2, randomblob(65536));
  }
} {}
# verify only one file, and file size exceeds chunks size
do_test multiplex-2.7.10 { expr ([file size [multiplex_name test.db 0]] > 65536) } {1}
do_test multiplex-2.7.11 { file exists [multiplex_name test.db 1] }                {0}
do_test multiplex-2.7.12 { db close }                                              {}
do_test multiplex-2.7.13 { sqlite3_multiplex_shutdown }                            {SQLITE_OK}


#-------------------------------------------------------------------------
# Try some tests with more than one connection to a database file. Still
# in rollback mode.
#
#   multiplex-3.1.*: Two connections to a single database file.
#